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You can use my plugin flutter_inappwebview, which is a Flutter plugin that allows you to add inline WebViews or open an in-app browser window and has a lot of events, methods, and options to control WebViews. To get HTML data, you can simply use var html = await controller.
Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project. Step 2 − Add the following code to res/layout/activity_main. xml. In the above code, we have taken web view to show html content.
The loadUrl() and loadData() methods of Android WebView class are used to load and display web page.
Actually this question has many answers. Here are 2 of them :
public class TestActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.webview);
final WebView webview = (WebView) findViewById(R.id.browser);
webview.getSettings().setJavaScriptEnabled(true);
webview.addJavascriptInterface(new MyJavaScriptInterface(this), "HtmlViewer");
webview.setWebViewClient(new WebViewClient() {
@Override
public void onPageFinished(WebView view, String url) {
webview.loadUrl("javascript:window.HtmlViewer.showHTML" +
"('<html>'+document.getElementsByTagName('html')[0].innerHTML+'</html>');");
}
});
webview.loadUrl("http://android-in-action.com/index.php?post/" +
"Common-errors-and-bugs-and-how-to-solve-avoid-them");
}
class MyJavaScriptInterface {
private Context ctx;
MyJavaScriptInterface(Context ctx) {
this.ctx = ctx;
}
public void showHTML(String html) {
new AlertDialog.Builder(ctx).setTitle("HTML").setMessage(html)
.setPositiveButton(android.R.string.ok, null).setCancelable(false).create().show();
}
}
}
This way your grab the html through javascript. Not the prettiest way but when you have your javascript interface, you can add other methods to tinker it.
The option you choose also depends, I think, on what you intend to do with the retrieved html...
In KitKat and above, you could use evaluateJavascript method on webview
wvbrowser.evaluateJavascript(
"(function() { return ('<html>'+document.getElementsByTagName('html')[0].innerHTML+'</html>'); })();",
new ValueCallback<String>() {
@Override
public void onReceiveValue(String html) {
Log.d("HTML", html);
// code here
}
});
See this answer for more examples
For android 4.2, dont forget to add @JavascriptInterface to all javascript functions
Android WebView is just another render engine that render HTML contents downloaded from a HTTP server, much like Chrome or FireFox. I don't know the reason why you need get the rendered page (or screenshot) from WebView. For most of situation, this is not necessary. You can always get the raw HTML content from HTTP server directly.
There are already answers posted talking about getting the raw stream using HttpUrlConnection or HttpClient. Alternatively, there is a very handy library when dealing with HTML content parse/process on Android: JSoup, it provide very simple API to get HTML contents form HTTP server, and provide an abstract representation of HTML document to help us manage HTML parsing not only in a more OO style but also much easily:
// Single line of statement to get HTML document from HTTP server.
Document doc = Jsoup.connect("http://en.wikipedia.org/").get();
It is handy when, for example, you want to download HTML document first then add some custom css or javascript to it before passing it to WebView for rendering. Much more on their official web site, worth to check it out.
One touch point I found that needs to be put in place is "hidden" away in the Proguard configuration. While the HTML reader invokes through the javascript interface just fine when debugging the app, this works no longer as soon as the app was run through Proguard, unless the HTML reader function is declared in the Proguard config file, like so:
-keepclassmembers class <your.fully.qualified.HTML.reader.classname.here> {
public *;
}
Tested and confirmed on Android 2.3.6, 4.1.1 and 4.2.1.
Android will not let you do this for security concerns. An evil developer could very easily steal user-entered login information.
Instead, you have to catch the text being displayed in the webview before it is displayed. If you don't want to set up a response handler (as per the other answers), I found this fix with some googling:
URL url = new URL("https://stackoverflow.com/questions/1381617");
URLConnection con = url.openConnection();
Pattern p = Pattern.compile("text/html;\\s+charset=([^\\s]+)\\s*");
Matcher m = p.matcher(con.getContentType());
/* If Content-Type doesn't match this pre-conception, choose default and
* hope for the best. */
String charset = m.matches() ? m.group(1) : "ISO-8859-1";
Reader r = new InputStreamReader(con.getInputStream(), charset);
StringBuilder buf = new StringBuilder();
while (true) {
int ch = r.read();
if (ch < 0)
break;
buf.append((char) ch);
}
String str = buf.toString();
This is a lot of code, and you should be able to copy/paster it, and at the end of it str will contain the same html drawn in the webview. This answer is from Simplest way to correctly load html from web page into a string in Java and it should work on Android as well. I have not tested this and did not write it myself, but it might help you out.
Also, the URL this is pulling is hardcoded, so you'll have to change that.
Why not get the html first then pass it to the web view?
private String getHtml(String url){
HttpGet pageGet = new HttpGet(url);
ResponseHandler<String> handler = new ResponseHandler<String>() {
public String handleResponse(HttpResponse response) throws ClientProtocolException, IOException {
HttpEntity entity = response.getEntity();
String html;
if (entity != null) {
html = EntityUtils.toString(entity);
return html;
} else {
return null;
}
}
};
pageHTML = null;
try {
while (pageHTML==null){
pageHTML = client.execute(pageGet, handler);
}
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return pageHTML;
}
@Override
public void customizeWebView(final ServiceCommunicableActivity activity, final WebView webview, final SearchResult mRom) {
mRom.setFileSize(getFileSize(mRom.getURLSuffix()));
webview.getSettings().setJavaScriptEnabled(true);
WebViewClient anchorWebViewClient = new WebViewClient()
{
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
super.onPageStarted(view, url, favicon);
//Do what you want to with the html
String html = getHTML(url);
if( html!=null && !url.equals(lastLoadedURL)){
lastLoadedURL = url;
webview.loadDataWithBaseURL(url, html, null, "utf-8", url);
}
}
This should roughly do what you want to do. It is adapted from Is it possible to get the HTML code from WebView and shout out to https://stackoverflow.com/users/325081/aymon-fournier for his answer.
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